Operating System, Question Paper of BSC IT (D) 1st Semester,Download Previous Years Question Paper 2

Roll No……..

Total No. of Questions: 13

Paper ID [A0303]

B.Sc.IT (05)- 103 B.Sc. CST- 404 (Old) (Sem.-1^st)

B.Sc.IT – 201 (Old)/302 (New)/DCA-204 (New)

OPERATING SYSTEM

         

Time: 3 Hrs.                                                        Max. Marks: 75

Instruction to Candidates:

1. Section-A is Compulsory.

2. Attempt any Nine questions from Section-B.

SECTION-A

Q1.

          (a) What are the two main functions of an operating system?

          (b) What is the principal disadvantage of too much multi-programming?

          (c) What is starvation? How it is removed in priority scheduling?

          (d) Differentiate user level threads from kernel level threads.

          (e) What is binary semaphore and why it is used?

          (f) Which is the best condition to prevent from a deadlock?

          (g) Define the concept of dynamic loading.

          (h) What is compaction and why it is used?

          (i) What is Belady’s anomaly problem?

          (j) What is the difference between local page replacement and global page           replacement?

          (k) How interrupt differ from trap?

          (l) Differentiate record, file and directory.

          (m) What is indexed access?

          (n) What is the purpose of system call?

          (o) How schedulers differ from dispatcher?

SECTION-B

Q2.    What is operating system? Explain different function of operating system.

Q3.    Explain different types of scheduling queues and types of schedules.

Q4.    Consider the following set of processes, with the length of CPU-burst time        given in milliseconds:

Process	Burst Time	Priority
P1	10	3
P2	29	1
P3	3	3
P4	7	4
P5	12	2

          The processes are assumed to have arrived in the order P1,P2,P3,P4,P5 all at   time 0.

          (a) What is the turnaround time of each process for using FCFS, SJF, a non-          preemptive priority (a smaller priority number implies a higher priority) and    RR (quantum=10) scheduling.

          (b) What is the waiting time of each process for each of the scheduling     algorithm in part a.

Q5.    Explain Dining Philosopher problem in process synchronization.

Q6.    What are the four necessary conditions to occur a deadlock? Explain bankers           algorithm.

Q7.    Explain the segmentation memory management scheme in detail.

Q8.    What is the cause of thrashing? How it occur and explain different methods      to prevent from thrashing?

Q9.    (a) Why are page sizes always power of 2?

          (b) Consider a logical address space of eight pages  of 10234 words each,          mapped onto a physical memory of 32 frames. How many bits are there in the logical address and physical address?

Q10. Consider the following page reference string:

          7,0,1,2,0,3,0,4,2,3,0,3,2,1,2,0,1,7,0,1.

          How many page faults would occur for the following replacement algorithms, assuming three frames? Remember that all frames are initially     empty,

          (a) LRU replacement

          (b) FIFO replacement

          (c) Optimal replacement

Q11. Explain the different operations performed on files.

Q12. Explain Direct Memory Access and steps in a DMA transfer.

Q13.  Compare parallel processor systems with distributed systems.